In this study, footprint and ground reaction forces (GRF) were simultaneously recorded from 32 male subjects running barefoot. Angle between the rearfoot and the forefoot in static (αS) and in running (αR) conditions, and orientation of both, rearfoot (αrf) and forefoot(αff) with the direction of running (DOR), were measured and correlated to selected GRF parameters. The dynamic rearfoot/forefoot angle (αR) was correlated, positively with arch deformation (r = 0.58, P < 0.001), vertical Fz loading peak (r = 0.60, P < 0.001), mediolateral, and anteroposterior force rates (r = 0.47 and 0.48, P< 0.01), and negatively with stance time (r = -0.41, P < 0.05) and total course of the force application point path (r = -0.71, P< 0.001). Both a medial and a lateral rotation were observed on footprint between the rearfoot and the forefoot in the horizontal plane. A medially rotated forefoot (“closed foot”) was associated to a rigid and inverted foot, whereas a laterally rotated forefoot (“open foot”) was associated to a flexible and everted foot.
Laboratoire de Physiologie de l'Exercice, Centre de Recherche en Biomécanique Articulaire, Faculté de Médecine Lyon-Sud, 69921 Oullins, FRANCE
Submitted for publication June 1994.
Accepted for publication April 1995.
This study was supported by Decathlon Production, Footwear Department.
Address for correspondence: Philippe Freychat, Decathlon Production Footwear Department, 4 Boulevard de Mons, 59665 Villeneuve d'Ascq, Cedex, France.